The oil trials charted here dosed between 0.5 and 5 grams a day for no longer than 3 months: 2 grams for dry eyes, 3 grams for vaginal dryness, 0.5 or 2 grams for skin, 4 grams for 33 to 35 days in a 2013 metabolomics crossover, and 5 grams in a 4-week platelet study of 12 men. A 2020 dose-escalation study dosed palmitoleic acid in milligrams, up to 1520 mg a day, and its abstract does not give grams of oil. This reference table records the exact dose, form, split, and duration of every trial charted here, so label claims can be checked against what was actually tested rather than what sounds good. The 2022 lipid meta-analysis gives no single dose to copy, and the 0.75 ml blood-pressure trial was retracted in 2026, so that row stays only as a marker.
The dose-by-trial table
Every trial in the table below carries an evidence grade in our research file. This page just lines those same studies up by dose.
| Trial | Daily dose | Form | Split | Duration |
|---|---|---|---|---|
| Larmo 2010 (dry eye) | 2 g | Seed+berry oil blend | 1 g twice daily with meals | 3 months |
| Jarvinen 2011 (mechanism) | 2 g | Same cohort, same oil | 1 g twice daily with meals | 3 months |
| Yang 2009 (skin) | 2 g | SBA24 oil, oral arm | Not specified | 3 months |
| Chan 2024 (skin) | 0.5 g | Omegia fruit-and-seed oil blend vs palm oil placebo | One softgel a day | 12 weeks |
| Larmo 2014 (vaginal) | 3 g | Sea buckthorn oil vs placebo oil (form not stated in the abstract) | Not specified | 3 months |
| Larmo 2008 (infections) | 28 g | Berry puree (food dose) | Not stated in the abstract | 3 months |
| Morone 2026 (constipation) | 500 mg | Concentrated fruit extract vs placebo, not an oil | One capsule daily | 28 days |
| Vashishtha 2017 (hypertension). RETRACTED 2026, not usable as evidence | 0.75 ml | Seed oil | Single daily dose | 30 days |
| Larmo 2013 (metabolomics) | 4 g oil, or 20 g dried berries, 14.6 g phenolic extract with maltodextrin, or 100 g frozen bilberries | Seed-and-pulp oil blend (8 capsules), dried berries, extract or bilberries, one diet per period, no placebo | Not stated | 33 to 35 days per diet, crossover |
| Huang 2020 (dose escalation) | 380, 760 and 1520 mg of cis-palmitoleic acid, or 120, 240 and 480 mg of the trans isomer. Grams of oil not given in the abstract | Sea buckthorn oils high in cis-palmitoleic acid, or oils augmented in the trans isomer, crossover | Not stated in the abstract | 3 weeks per dose, 4-week washout |
| Johansson 2000 (platelets) | 5 g | Berry oil, crossover against a coconut-oil control | Not stated in the abstract | 4 weeks |
| Geng 2022 (lipid meta-analysis) | No single dose | Sea buckthorn supplementation, pooled from 15 trials | Not applicable | Not applicable |
See the data behind this chart
| Trial / goal | Daily dose |
|---|---|
| Dry eyes (Larmo 2010) | 2 g oil, 3 months |
| Skin aging (Yang 2009) | 2 g oil, 3 months |
| Skin (Chan 2024) | 0.5 g oil (one 500 mg softgel), 12 weeks |
| Vaginal dryness (Larmo 2014) | 3 g oil, 3 months |
| Platelets (Johansson 2000) | 5 g oil, 12 men, 4 weeks (highest dose in these trials) |
Reading the splits and forms
Two details in the table deserve a second look. First, the split: the dry-eye trial divided its 2 grams into two 1-gram servings with meals, the 2024 skin trial gave one softgel a day, and several trials do not say how the dose was split. The oil’s carotenoids and vitamin E are fat-soluble, so taking it with a meal is a sensible habit and the practical pages suggest it, but only the dry-eye trial was designed around meals.
Second, the form: every oil trial used a defined product, a blend, a branded oil, or straight berry oil, dosed in grams. The berry trial used actual fruit at food quantity. When a label cites “clinical doses,” this table is the yardstick: 0.5 to 3 grams of named oil, not a sprinkle of powder in a proprietary blend.
Third, the ceiling shape: no trial in the table that gives its dose in grams went above 5 grams, and the 5-gram test lasted four weeks in 12 healthy men. The 2020 dose-escalation study gave its doses in milligrams of palmitoleic acid and its abstract does not give grams of oil, so it cannot be placed on that scale. Doses beyond the table are not bold, they are unmapped.
The dose ladder, in everyday terms
Grams of oil are abstract, so translate them before you shop. Half a gram, one standard 500 mg softgel, is the smallest dose in the table, used in the 2024 skin study, and one gram is two softgels. Two grams, the dry-eye dose, is four softgels or a scant half teaspoon of liquid. Three grams, the vaginal-dryness dose and the largest in the benefit trials, is six softgels. Five grams, the highest dose in grams in these trials, is ten softgels a day, and it produced the platelet effect the blood-thinner page is built around. The 28 grams of berry puree in the infection trial is about two heaped tablespoons, a small handful of fruit’s worth: food, not a capsule.
Four rules for reading the table
The studied oil range is 0.5 to 3 grams. The dry-eye, skin, and vaginal-dryness trials all landed there, which is why the dosage page and the how much daily guide both steer you into that window and no higher. It is the range that was tested, not a promise that every dose in it works.
Five grams is a ceiling marker, not a target. The only 5-gram study in the table produced a measurable antiplatelet effect in 12 healthy men. It exists to mark the boundary, not to invite anyone near it.
With a meal is the sensible habit. The oil’s carotenoids and vitamin E are fat-soluble, and the dry-eye trial dosed twice daily with meals by design, so we suggest the same. The table does not show that an empty stomach changes the result.
Duration is part of the dose. Three months is not a minimum course, it is the longest any trial in the table ran. The dry-eye trial measured its effect at the end of winter, not after week one, so expect the studied timeline rather than an overnight change, and treat anything past three months as personal experiment rather than evidence.
Why no trial went past three months
The 3-month ceiling is not a finding. It is a budget line. Academic trials run on grants sized in semesters, not years, and every added month costs participants, capsules, and lab work. Safety caution pulls the same direction: review boards approve longer exposures only after shorter ones look clean, and sea buckthorn’s shorter trials finished barely a decade ago. The practical consequence belongs to you: everything this site says about benefits and safety lives inside 12 weeks of daily use. What happens in month six, or year six, nobody has measured, and any page that implies otherwise is guessing on your behalf.
The dose a label implies versus the dose tested
The commonest label trick is dose theater: a capsule that contains sea buckthorn somewhere in a proprietary blend, at a fraction of a gram, borrowing the credibility of trials that dosed grams. The blend lists the ingredient, the front panel implies the benefit, and the dose that produced the benefit never appears. The audit takes one question: how many grams of named sea buckthorn oil per day, and does that number appear in the table above? If the label will not say, the answer is closer to a few drops than to the 2-gram row. The reading-studies page counts dose realism as one of its six checks for exactly this reason.
What would settle dosing
The missing trial is a dose-ranging study: the same oil at 1, 2, and 4 grams a day, about 90 people per arm, six months, one primary outcome. That single experiment would answer whether 2 grams beats 1, whether 4 grams beats 2 or just costs more, and where benefit flattens against the platelet signal the 5-gram study found. Until it exists, the table on this page is the whole dosing map, and the cholesterol meta-analysis page shows why the pooled lipid result gives no single dose.
Using this table as a lie detector
When a product implies benefit at one softgel a day, check the table: the dry-eye, vaginal-dryness and 2009 skin trials used 4 to 6 softgels’ worth of oil, the one trial that gave a single softgel found only two small skin changes against placebo, and the capsules that match these grams are the ones whose label math survives that check. When a protocol suggests mega-dosing, check the ceiling row. The full trial context behind each row lives in the clinical trials catalog, and the safety synthesis is on the safety review page.
The same table disciplines expectations in the other direction. If you take 1 gram a day and feel nothing at week two, the trials say that proves nothing, because none of them measured week two. If you take 3 grams for three months and your lipids were normal to begin with, the pooled data says the likely change is also nothing, because the effects concentrate in abnormal baselines. Dose, duration, and starting point are the three dials every row in the table sets.
Frequently asked questions
What doses did the sea buckthorn studies use?
The dry-eye trial used 2 grams of oil daily, the vaginal-dryness trial 3 grams, and the two skin trials 2 grams and one 500 mg softgel. The 2022 lipid meta-analysis pooled 15 trials and reports high heterogeneity, so it gives no single dose to copy. The highest dose in grams in the human trials we cite was 5 grams of berry oil daily for 4 weeks, which produced a measurable antiplatelet effect. The 2020 dose-escalation study gave milligrams of palmitoleic acid, and its abstract does not give grams of oil. The 2026 constipation trial is the odd one out at 500 mg of a concentrated fruit extract, which does not convert into an oil dose. We treat 3 grams, the largest dose in the dry-eye, skin and vaginal-dryness trials, as the practical ceiling for daily oil.
How do the studied doses convert to softgels?
At 500 mg per softgel, 0.5 gram is 1 softgel, 2 grams is 4, and 3 grams is 6. The dry-eye trial split its 2 grams as 1 gram twice daily with meals. One level teaspoon of liquid oil is about 4.5 grams, above the 3-gram ceiling, so measure with a real spoon and take it with food.
Is more than 3 grams a day unsafe?
Unstudied is the word, not unsafe. The 5-gram study measured a platelet effect in 12 healthy men and its abstract mentions no harm, and a 2013 crossover gave 4 grams a day for 33 to 35 days to track blood metabolites, so the space between 3 and 5 grams is only thinly mapped. The practical ceiling stays at 3 grams because that is the largest dose in the benefit trials we cite and because none of the trials we cite watched a higher dose for longer than about five weeks.
Illustration.